Water-soluble laminated films are known for many uses. For example, they may be used for packaging. The packages are simply added to water, the packaging dissolves or disperses and the contents of the package are released. Laminated films comprise a plurality of different layers and may have certain advantages over single films. For example, GB-A-2,244,258 teaches that a water-soluble laminated film may be used to package a hazardous chemical dissolved or dispersed in a liquid or gel. While a single film may have pinholes, the two films in a laminate are unlikely to have pinholes which coincide. Thus the risk of leakage is reduced by using a laminated film.
There are many known processes for producing films which can then be laminated. If two or more identical films, or films of the same polymer, are laminated together, the films are generally made by the same process, for example by extrusion blowing or solution casting. This is also the case even if two or more different films are laminated together.